The following conclusions can be summarized: 1. The application of thermochemical calculation is a helpful tool for an estimation of phase compositions due to the reaction with affecting calcium aluminate melts at 1600°C. 2. For the applied lime-rich melt the erosion depths as an index for the wear rate are less in in case of pure alumina castables than for the castables with spinel addition. 3. The formation of dense CA_6 layers lead to a decreasing erosion resp. to a better corrosion resistance due to slow solid-solid diffusion through this layer. This behaviour was found for the alumina based castables with no spinel addition. 4. The lime-rich melt reacts with the alumina forming CaO·6Al_2O_3 (CA_6). The dense habit of CA_6 layers suppresses further erosion of the material. 5. The castables based on alumina with different spinel contents reveal a formation of a porous spinel layer at the interface from where CA_6 crystals precipitate due to the alumina-rich spinel addition. 6. The various content of spinel influences the wear rate of the castables in a good correlation to other studies.
展开▼
